DRYING AND PACKING RUBBER FOR EXPORT. 



139 



heating shelves or pipes. At a very moderate temperature of 

 the material that is to be dried about 95 Fahr. (35 Cent.) 



the water, owing to the vacuum, begins to evaporate briskly 

 out of the substances, and the latter dry rapidly. 



" Even materials which are very difficult to dry, and which by 



